This section introduces aspects that may be helpful to facilitating a better understanding of the inventions. Accordingly, the statements of this section are to be read in this light. The statements of this section are not to be understood as admissions about what is in the prior art or what is not in the prior art.
Optical beam steerers are often based on micro-electrical mechanical systems (MEMS), liquid crystal (LC) systems, acousto-optic (AO) systems, electro-optic (EO) systems, or injection locked laser systems, such as vertical cavity surface emitting lasers (VESEL). Each of these approaches to Optical beam steering can have problems, however. For instance, the speed of MEMS may be too slow for many video applications and even slower for applications that require precise analog steering. MEMS also cannot readily create multiple beams. The beam quality of LC systems can be high, can generate multiple beams, and the steering speed is fast enough for video. LC systems, however, are highly temperature sensitive and may not be amenable to integration with other optical components such as lasers. While steering can be fast, and the beam quality can be good, it may be difficult to steer in two dimensions and/or create multiple beams with an AO system. While the speed can be fast, EO beam steering at present appears to be limited to one-dimensional (1D) steering. The drawback to using VCSELs for beam steering with a photonic integrated circuit (PIC) is that they may be difficult to injection-lock using planar waveguides with a prescribed optical phase offset, and, it may be difficult to introduce individual electronic phase control.